start-frontend.sh

#!/usr/bin/env bash
# ============================================================================
# LAION-Tunes Frontend Startup Script
# ============================================================================
# Serves the LAION-Tunes web UI via HTTPS using Caddy as a reverse proxy.
# Caddy serves index.html for the root and proxies /api/* requests to the
# FastAPI backend, then cloudflared provides a public HTTPS tunnel.
#
# Usage:
#   ./start-frontend.sh                          # defaults
#   ./start-frontend.sh --port 8080              # custom frontend port
#   ./start-frontend.sh --backend http://host:7860  # custom backend URL
#
# Prerequisites:
#   - caddy (available at /root/.local/bin/caddy)
#   - cloudflared binary at ../cloudflared
#   - Backend must be running (start-backend.sh)
# ============================================================================

set -euo pipefail

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
cd "$SCRIPT_DIR"

# ── Configuration ────────────────────────────────────────────────────────────
FRONTEND_PORT="${FRONTEND_PORT:-8080}"
BACKEND_URL="${BACKEND_URL:-http://localhost:7860}"
CADDY="$(command -v caddy 2>/dev/null || echo /root/.local/bin/caddy)"
CLOUDFLARED="$SCRIPT_DIR/../cloudflared"
LOG_DIR="$SCRIPT_DIR/logs"

# Parse args
while [[ $# -gt 0 ]]; do
    case "$1" in
        --port) FRONTEND_PORT="$2"; shift 2 ;;
        --backend) BACKEND_URL="$2"; shift 2 ;;
        *) echo "Unknown arg: $1"; exit 1 ;;
    esac
done

mkdir -p "$LOG_DIR"

echo "============================================================"
echo " LAION-Tunes Frontend Startup"
echo "============================================================"
echo " Frontend port:  $FRONTEND_PORT"
echo " Backend URL:    $BACKEND_URL"
echo " Caddy:          $CADDY"
echo "============================================================"

# ── Verify prerequisites ─────────────────────────────────────────────────────
if [ ! -x "$CADDY" ]; then
    echo "ERROR: caddy not found at $CADDY"
    echo "Install: curl -fsSL https://caddyserver.com/api/download?os=linux&arch=amd64 -o /usr/local/bin/caddy && chmod +x /usr/local/bin/caddy"
    exit 1
fi

if [ ! -x "$CLOUDFLARED" ]; then
    echo "ERROR: cloudflared not found at $CLOUDFLARED"
    exit 1
fi

if [ ! -f "$SCRIPT_DIR/index.html" ]; then
    echo "ERROR: index.html not found in $SCRIPT_DIR"
    exit 1
fi

# ── Step 1: Check backend is reachable ───────────────────────────────────────
echo ""
echo "[1/3] Checking backend connectivity..."
if curl -sf "${BACKEND_URL}/api/stats" >/dev/null 2>&1; then
    echo "  Backend is reachable at $BACKEND_URL"
else
    echo "  WARNING: Backend not reachable at $BACKEND_URL"
    echo "  Make sure start-backend.sh is running first."
    echo "  Continuing anyway (Caddy will retry automatically)..."
fi

# ── Step 2: Start Caddy reverse proxy ────────────────────────────────────────
echo ""
echo "[2/3] Starting Caddy on port $FRONTEND_PORT..."

# Kill existing caddy on this port
fuser -k "${FRONTEND_PORT}/tcp" 2>/dev/null || true
sleep 1

# Write Caddyfile
cat > "$SCRIPT_DIR/Caddyfile" <<CADDYEOF
{
    admin off
    auto_https off
}

:${FRONTEND_PORT} {
    # Serve static files (index.html, nsfw report, etc.)
    root * ${SCRIPT_DIR}

    # Proxy all API requests to the FastAPI backend
    handle /api/* {
        reverse_proxy ${BACKEND_URL}
    }

    # Proxy the NSFW report page
    handle /nsfw-report {
        reverse_proxy ${BACKEND_URL}
    }

    # Serve index.html for root
    handle {
        try_files {path} /index.html
        file_server
    }

    # Enable gzip
    encode gzip

    # CORS headers (backend already handles this, but belt-and-suspenders)
    header {
        Access-Control-Allow-Origin *
        Access-Control-Allow-Methods "GET, POST, OPTIONS"
        Access-Control-Allow-Headers "Content-Type"
    }

    log {
        output file ${LOG_DIR}/caddy-access.log
    }
}
CADDYEOF

nohup "$CADDY" run --config "$SCRIPT_DIR/Caddyfile" \
    > "$LOG_DIR/caddy.log" 2>&1 &

CADDY_PID=$!
echo "  Caddy PID: $CADDY_PID"
echo "$CADDY_PID" > "$LOG_DIR/caddy-frontend.pid"

# Wait for Caddy to start
sleep 2
if curl -sf "http://localhost:${FRONTEND_PORT}/" >/dev/null 2>&1; then
    echo "  Caddy ready."
else
    echo "  WARNING: Caddy may not be ready yet. Check: tail -f $LOG_DIR/caddy.log"
fi

# ── Step 3: Start cloudflared tunnel for public HTTPS ────────────────────────
echo ""
echo "[3/3] Starting cloudflared tunnel for public HTTPS..."

# Kill existing tunnel if running
if [ -f "$LOG_DIR/cloudflared-frontend.pid" ]; then
    kill "$(cat "$LOG_DIR/cloudflared-frontend.pid")" 2>/dev/null || true
fi

nohup "$CLOUDFLARED" tunnel --url "http://localhost:${FRONTEND_PORT}" \
    > "$LOG_DIR/cloudflared-frontend.log" 2>&1 &

CF_PID=$!
echo "$CF_PID" > "$LOG_DIR/cloudflared-frontend.pid"

# Wait for tunnel URL
sleep 5
TUNNEL_URL=""
for i in $(seq 1 30); do
    TUNNEL_URL=$(grep -oP 'https://[a-z0-9-]+\.trycloudflare\.com' "$LOG_DIR/cloudflared-frontend.log" 2>/dev/null | head -1)
    if [ -n "$TUNNEL_URL" ]; then
        break
    fi
    sleep 1
done

echo ""
echo "============================================================"
echo " LAION-Tunes Frontend is running!"
echo "============================================================"
echo ""
echo " Local:    http://localhost:${FRONTEND_PORT}"
if [ -n "$TUNNEL_URL" ]; then
    echo " Public:   $TUNNEL_URL"
else
    echo " Public:   (tunnel URL pending, check: grep trycloudflare $LOG_DIR/cloudflared-frontend.log)"
fi
echo ""
echo " Logs:"
echo "   Caddy:        tail -f $LOG_DIR/caddy.log"
echo "   Access:       tail -f $LOG_DIR/caddy-access.log"
echo "   Cloudflared:  tail -f $LOG_DIR/cloudflared-frontend.log"
echo ""
echo " Stop everything:"
echo "   kill $CADDY_PID $CF_PID"
echo "============================================================"